The Arnold Hague database of SL convoys: The SL series ran from Freetown to the UK from September 1939 throughout the war without cancellation.

From May 1943, the MKS convoy from Gibraltar would rendezvous with the SL convoy and the combined convoy would proceed to the UK.
In addition to the MKS convoys, the following joined from Gibraltar:
SL.91G
SL.97G
SL.103G
SL.120G
SL.124G
SL.127G
SL STATUS
Convoys
287
Ship Entries
8,800
Escort Duties
2,140